A centrifugal casting mold for a sphere

Abstract

The utility model relates to a kind of sphere centrifugal casting mould, including outer mould and inner mould, outer mould is manufactured using ordinary steel material, inner mould is manufactured using high-temperature-resistant steel material, outer mould is connected fixedly with the mounting disc of horizontal centrifuge rotating shaft and outer mould cylinder, outer mould cylinder is equipped with inner mould mounting hole, and its one end is fixedly connected in the inner plane of mounting disc side;Its characterized is that: inner mould is composed of left half mould and right half mould, and is integrally embedded in the inner hole of outer mould cylinder;Left half mould and right half mould contact surface side symmetrical arrangement hemispherical inner cavity;Right half mould center is equipped with the pouring hole of intercommunication hemispherical inner cavity, and locking device is set between outer mould cylinder and inner mould.Casting process avoids sand mould, wax mould material loss, and when casting different size sphere, outer mould can be universal, mould manufacturing material and installation, replacement time are saved.Casting process is environmental protection, product quality is good, production efficiency is high, product cost is low and other advantages.

Description

Technical Field

[0001] This utility model relates to a centrifugal casting mold for a key component of a valve, and more particularly to a centrifugal casting mold for a ball valve ball. Background Technology

[0002] The quality of the valve body and ball is a key factor determining the quality of ball valve products. Currently, the ball and valve body of ball valves used in low-pressure applications are generally manufactured using casting, while those used in high-pressure applications are generally manufactured using forging. Common casting processes include sand casting and wax casting. Balls produced by these processes often have defects such as sand holes and air bubbles, resulting in low density and low pressure resistance. Therefore, they are only suitable for low-pressure valve products. Furthermore, the consumption of sand and wax is high, with molten iron loss reaching 35-40% during casting, leading to significant material waste and substantial environmental pollution. Therefore, this process is listed as a restricted development area. Forging, on the other hand, uses steel profiles to form a solid spherical blank through multiple forging processes, which is then machined and ground. This process produces balls with high density and good pressure resistance, making it suitable for high-pressure valve products. However, it suffers from low production efficiency, significant material waste, and high manufacturing costs. Utility Model Content

[0003] The purpose of this invention is to address the shortcomings of existing technologies by providing a spherical centrifugal casting mold that is environmentally friendly, improves the density of castings, has low molten iron loss, low material loss, high production efficiency, and low product cost during the casting process.

[0004] The technical solution to achieve the purpose of this utility model is as follows: A spherical centrifugal casting mold includes an outer mold and an inner mold. The outer mold is made of ordinary steel, and the inner mold is made of high-temperature resistant steel. The outer mold consists of a mounting plate fixedly connected to the shaft of a horizontal centrifuge and an outer mold column. The outer mold column has an inner mold mounting hole, and one end of the column is fixedly connected to a plane on one side of the mounting plate. The inner mold consists of a left half mold and a right half mold, which are integrally embedded in the inner hole of the outer mold column. A hemispherical inner cavity is symmetrically arranged on one side of the contact surface between the left half mold and the right half mold. A casting hole communicating with the hemispherical inner cavity is provided in the center of the right half mold. A locking device is provided between the outer mold column and the inner mold.

[0005] Ideally, the mounting plate has a demolding hole at its center, and a push rod is installed inside the demolding hole. The push rod is a hydraulic push rod inside the central hole of the centrifuge shaft. The hydraulic push rod and the central hole of the centrifuge shaft form a hydraulic piston mechanism, which is controlled by the centrifuge hydraulic system.

[0006] Ideally, the outer circular surface of the right half of the mold and the inner hole of the outer mold cylinder should be fitted together by a conical surface that gradually expands from left to right.

[0007] Ideally, an anti-rotation positioning device is provided between the outer circular surfaces of the left and right half molds and the outer mold column. The anti-rotation positioning device is composed of an axial positioning rib on the inner wall of the outer mold column and an axial positioning groove on the outer circular surface of the inner mold.

[0008] Preferably, the left end face of the right half mold is provided with a shaft hole casting rod mounting cavity, the right cavity wall of the shaft hole casting rod mounting cavity is provided with a transverse positioning groove, and the upper right side plane of the shaft hole casting rod is provided with a transverse positioning shoulder that cooperates with the transverse positioning groove; the middle left side of the shaft hole casting rod is provided with a spherical arc that matches the hemispherical inner cavity of the left half mold.

[0009] The advantages of this invention compared to existing technologies are as follows: the sphere is produced using a centrifugal casting process, and the mold consists of a metal outer mold and a metal inner mold. This method is environmentally friendly, produces spheres with high density, and avoids material waste associated with sand and wax molds. Furthermore, when casting spheres of different sizes, only the inner mold with the corresponding inner cavity diameter needs to be replaced; the outer mold is interchangeable and does not require disassembly, saving on mold manufacturing materials and installation / replacement time. This invention offers advantages such as an environmentally friendly casting process, high product quality, high production efficiency, and low product cost. Attached Figure Description

[0010] Figure 1 This is a cross-sectional view of the mold structure of the present invention.

[0011] In the diagram: 1. Mounting plate, 2. Outer mold column, 3. Left half mold, 4. Right half mold, 5. Sphere, 6. Casting hole, 7. Spherical inner cavity, 8. Demolding hole. Detailed Implementation

[0012] like Figure 1The centrifugal casting mold for the sphere shown includes an outer mold and an inner mold. The outer mold is made of ordinary steel, and the inner mold is made of high-temperature resistant steel to reduce the manufacturing cost of the mold. The outer mold consists of a mounting plate 1 fixedly connected to the centrifuge shaft and an outer mold column 2. The centrifuge adopts a horizontal structure. The outer mold column 2 has an inner mold mounting hole, one end of which is fixedly connected to a plane on one side of the mounting plate 1. The center line of the inner mold mounting hole forms a horizontal direction. The mounting plate 1 and the outer mold column 2 can be manufactured as a single piece, or the outer cylindrical surface of one end of the outer mold column 2 can be inserted into the mounting recess of the mounting plate 1 for fixed connection, or it can be welded together. After welding, the inner hole of the outer mold column 2 is precision machined to eliminate the influence of welding temperature effect. The mounting plate 1 and the outer mold column 2 are installed concentrically with the centrifuge shaft. Its characteristic is that the inner mold is made of... The mold consists of a left half mold 3 and a right half mold 4, which are fitted into the inner hole of the outer mold column 2. A hemispherical inner cavity is symmetrically arranged on one side of the contact surface between the left half mold 3 and the right half mold 4. The center of the right half mold 4 is provided with a casting hole 6 that connects to the hemispherical inner cavity. The diameter of the casting hole 6 is smaller than the inner diameter of the through hole of the sphere 5. Molten iron is injected from the casting hole 6 into the spherical inner cavity 7 composed of the left half mold 3 and the right half mold 4. Under the condition of meeting the casting speed, the smaller the diameter of the casting hole 6, the less molten iron is lost due to splashing. Molten iron is continuously injected while the centrifugal casting mold rotates at high speed, so that the molten iron forms a spherical blank without pores and bubbles in the spherical inner cavity 7 under the action of centrifugal force. A locking device is set between the outer mold column 2 and the inner mold to lock the inner mold between the inner hole of the outer mold column 2 and the plane of the mounting plate 1, so as to prevent the inner mold and the outer mold from sliding relative to each other.

[0013] The technical advantages of this solution are that the spheres are centrifugally cast using metal molds, which improves the density of the product and avoids the material loss and environmental pollution associated with sand and wax casting. The outer mold is made of ordinary steel, which reduces the cost of mold manufacturing. Moreover, when casting spheres of different sizes, only the inner mold needs to be replaced. The outer mold is universal and does not need to be disassembled or replaced from the centrifuge, saving on mold manufacturing costs, improving production efficiency, and resulting in low product costs.

[0014] A demolding hole 8 is provided in the center of the mounting plate 1, and a push rod is installed in the demolding hole 8. The push rod is a hydraulic ejector rod in the center hole of the centrifuge shaft. The hydraulic ejector rod and the center hole of the centrifuge shaft form a hydraulic piston mechanism, which is controlled by the centrifuge hydraulic system. After the sphere 5 is cast, the centrifuge hydraulic system activates the hydraulic ejector rod to push the right half mold 4 out of the inner hole of the outer mold column 2, and the sphere 5 automatically rolls out of the inner cavity of the left half mold 3 for demolding.

[0015] The technical advantage of this technology is that by using a centrifuge for hydraulic automatic demolding, it solves the problems of high labor intensity and cumbersome operation in the existing manual demolding process, thereby improving production efficiency.

[0016] The outer circular surface of the right half mold 4 and the inner hole of the outer mold column 2 are fitted together by a conical surface that gradually expands from left to right. The conical surface can penetrate the entire inner hole of the outer mold column 2, or the part that fits with the right half mold 4 can be a conical surface and the part that fits with the left half mold 3 can be a cylindrical surface.

[0017] The technical effect of this feature is that during demolding, it reduces the separation friction between the inner and outer molds, lowers the demolding push or pull force, and makes demolding easy and effortless.

[0018] An anti-rotation positioning device is provided between the outer circular surfaces of the left half mold 3 and the right half mold 4 and the outer mold column 2. The anti-rotation positioning device is composed of an axial positioning rib on the inner wall of the outer mold column 2 and an axial positioning groove on the outer circular surface of the left half mold 3 and the right half mold 4.

[0019] The technical effect of this feature is that when the centrifuge rotates at high speed, the axial positioning ribs and axial positioning grooves cooperate with each other to prevent the left half mold 3 and the right half mold 4 from rotating relative to the outer mold column 2, thereby improving the reliability of the inner mold clamping installation.

[0020] The locking device consists of at least two locking pins positioned between the right end face of the right half mold 4 and the radial pin holes of the outer mold column 2, evenly distributed circumferentially. The locking pins can be manually inserted or hydraulically inserted, controlled by the centrifuge's hydraulic system to insert or remove them from the radial pin holes. The locking pins are wedge-shaped, inserted from the inside of the radial pin holes, and wedge-fitted with the radial pin holes under centrifugal force. By pressing the right end face of the right half mold 4 with the locking pins, the right half mold 4 can be press-fitted or released from the mold, ensuring reliable inner mold pressing and easy installation and removal. Alternatively, the locking device can consist of several fastening devices positioned between the right end face of the right half mold 4 and the outer mold column 2.

[0021] The casting mold of this utility model can also be installed on a vertical centrifuge. When installed on a vertical centrifuge, the right half mold 4 and the sphere 5 need to be pushed out from above the inner hole of the outer mold column 2.

[0022] The directional terms such as "left," "right," "up," and "down" used in this utility model are only for the directions shown in the accompanying drawings and should not be used as a limitation on the technical solution of this invention.

Claims

1. A spherical centrifugal casting mold, comprising an outer mold and an inner mold, wherein the inner mold is made of high-temperature resistant steel, and the outer mold consists of a mounting plate (1) fixedly connected to the centrifuge shaft and an outer mold column (2), wherein the outer mold column (2) is provided with an inner mold mounting hole, and one end of which is fixedly connected to a plane on one side of the mounting plate (1); characterized in that: The inner mold consists of a left half mold (3) and a right half mold (4), which are fitted into the inner hole of the outer mold column (2). The left half mold (3) and the right half mold (4) are symmetrically provided with hemispherical inner cavities on one side of their contact surfaces, and the two hemispherical inner cavities form a spherical inner cavity (7). The right half mold (4) has a casting hole (6) in the center that connects to the hemispherical inner cavity, and a locking device is provided between the outer mold column (2) and the inner mold.

2. A spherical centrifugal casting mold according to claim 1, characterized by: A demolding hole (8) is provided in the center of the mounting plate (1). A push rod is provided in the demolding hole (8). The push rod is a hydraulic push rod in the center hole of the centrifuge shaft. The hydraulic push rod and the center hole of the centrifuge shaft form a hydraulic piston mechanism. The hydraulic piston mechanism is controlled by the centrifuge hydraulic system.

3. A spherical centrifugal casting mold according to claim 1 or 2, characterized by: The outer circular surface of the right half mold (4) and the inner hole of the outer mold column (2) are fitted together by a cone surface that gradually expands from left to right.

4. A spherical centrifugal casting mold according to claim 1 or 2, characterized in that An anti-rotation positioning device is provided between the outer circular surface of the left half mold (3) and the right half mold (4) and the outer mold column (2). The anti-rotation positioning device is composed of an axial positioning rib on the inner wall of the outer mold column (2) and an axial positioning groove on the outer circular surface of the left half mold (3) and the right half mold (4).

5. A spherical centrifugal casting mold according to claim 3, wherein An anti-rotation positioning device is provided between the outer circular surface of the left half mold (3) and the right half mold (4) and the outer mold column (2). The anti-rotation positioning device is composed of an axial positioning rib on the inner wall of the outer mold column (2) and an axial positioning groove on the outer circular surface of the left half mold (3) and the right half mold (4).

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